My POSTMAN requests works, but my seemingly identical IDE requests don't

Question

PARTIALLY SOLVED - I changed the request from

requests.post(url, headers = headers, data = data)

to:

requests.post(url, headers = headers, json = data)

and now it works. I am not sure why...

Original Post:

The code I am using below continues to provide a response:

{"code":"422","details":"Unrecognized token 'adGroupId': was expecting (JSON String, Number, Array, Object or token 'null', 'true' or 'false'"}

I am able to get a successful response with POSTMAN, and am failing to see the difference between this and my requests vscode attempts. FWIW, I simply copy the request body from the IDE and pasted it into POSTMAN as 'raw'.

My 'request' library failing attempts in the IDE:

headers = {
  "Amazon-Advertising-API-ClientId": clientid,
  "Authorization": access,
  "Amazon-Advertising-API-Scope":scope,
  "Content-Type": "application/json"
}

data = {
  "adGroupId":adgroupid,
  "keywords": [
    {
      "keyword": "mini bricks",
      "matchType": "exact"
    }
  ]
}

response = requests.post(
  'https://advertising-api.amazon.com/v2/sp/keywords/bidRecommendations',
  headers = headers,
  data = data
)
print(response.text)

My successful POSTMAN request headers and body:

Request Headers
Amazon-Advertising-API-ClientId: ...
Authorization: ...
Amazon-Advertising-API-Scope: ...
Content-Type: application/json
Cache-Control: no-cache
Postman-Token: ...
Request Body
{
  "adGroupId":...,
  "keywords": [
    {
      "keyword": "mini bricks",
      "matchType": "exact"
    }
  ]
}